Construct Irregular Polygons with TI-84 Plus GeoMaster

You can use the GeoMaster DRAW menu on the TI-84 Plus graphing calculator to create irregular and regular polygons, circles, triangles, and many other basic geometric shapes. To create an irregular polygon, follow these steps:

Press [GRAPH][WINDOW][6] to select the Polygon tool from the DRAW menu.

Polygon in the upper-right corner of the screen indicates that the Polygon tool is active.

Use the arrow keys to move the cursor to the location on the screen where you want to construct the first point defining your polygon. Press [ENTER] to anchor this point.

As you move the cursor, its coordinates are displayed at the bottom of the screen, and the anchored point appears in the shape of a diamond, as illustrated in the first screen.

After pressing [ENTER] in this step, you can precisely locate the point by giving the calculator the coordinates of that point. You can also label the point.

Use the arrow keys to move the cursor to the location on the screen where you wish to construct the second point defining the polygon. Press [ENTER] to anchor this point.

The second screen illustrates this step. Notice that the dashed line between these points indicates that the polygon is not yet constructed.

Use the arrow keys to construct the remaining points that define the polygon. Press [ENTER] to anchor each point.

The third screen illustrates this step. Notice that the line joining the first and last points you constructed is a dashed line. This indicates that the construction of the polygon is not yet complete.

Press [ENTER] and move the cursor away from the object.

All sides of the polygon appear as solid lines indicating the construction of the polygon is complete.

After constructing a polygon, the Polygon tool remains active until you deactivate it. So if you want to construct more polygons, just follow Steps 2 through 5. When you are finished using this tool, you deactivate it by pressing [CLEAR] or by selecting another menu item.